Under the provisions of Section 119 of 35 U.S.C., Applicants hereby claim the benefit of the filing date of Federal Republic of Germany Patent Application Number 19845406.6, filed Oct. 2, 1998, which Application is hereby incorporated by reference.
The present invention relates to substituted 1,3-diaryl-2-pyridin-2-yl-3-(pyridin-2-ylamino)propanol derivatives and pharmaceutically tolerated salts and physiologically functional derivatives thereof.
Several classes of active compounds for treatment of adiposity and disturbances in lipid metabolism have already been described, e.g.,
polymeric adsorbers, such as cholestyramine,
benzothiazepines (WO 93/16055),
bile acid dimers and conjugates (EP 0 489 423), and
4-amino-2-ureido-pyrimidine-5-carboxamides (EP 0 557 879).
The object of the present invention is to provide further compounds displaying a therapeutically valuable hypolipidemic action. 
The present invention therefore relates to 1,3-diaryl-2-pyridin-2-yl-3-(pyridin-2-ylamino)propanol derivatives of formula (I) or salts thereof,
wherein:
Z is
xe2x80x94NHxe2x80x94(C1-C16-alkyl)-(Cxe2x95x90O)xe2x80x94,
xe2x80x94(Cxe2x95x90O)xe2x80x94(C1-C16-alkyl)-(Cxe2x95x90O)xe2x80x94, or
xe2x80x94(Cxe2x95x90O)-phenyl-(Cxe2x95x90O)xe2x80x94;
A1, A2, A3, A4, each independently of one another is an amino acid radical, or an amino acid radical which is mono- or polysubstituted by amino acid-protective groups;
E is xe2x80x94SO2xe2x80x94R4 or xe2x80x94COxe2x80x94R4;
R1 is phenyl, thiazolyl, oxazolyl, thienyl, thiophenyl, furanyl, pyridyl, or pyrimidyl, wherein the rings are unsubstituted, or substituted up to 3 times by F, Cl, Br, xe2x80x94OH, xe2x80x94CF3, xe2x80x94NO2, xe2x80x94CN, xe2x80x94OCF3, xe2x80x94(C1-C6)-alkyl, xe2x80x94Oxe2x80x94(C1-C6)-alkyl, xe2x80x94Sxe2x80x94(C1-C6)-alkyl, xe2x80x94SOxe2x80x94(C1-C6)-alkyl, xe2x80x94SO2xe2x80x94(C1-C6)-alkyl, xe2x80x94(C1-C6)-alkyl, xe2x80x94(C3-C6)-cycloalkyl, xe2x80x94COOH, xe2x80x94COOxe2x80x94(C1-C6)-alkyl, xe2x80x94COOxe2x80x94(C3-C6)cycloalkyl, xe2x80x94CONH2, xe2x80x94CONHxe2x80x94(C1-C6)-alkyl, xe2x80x94CON[(C1-C6)-alkyl]2, xe2x80x94CONHxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94NH2, xe2x80x94NHxe2x80x94COxe2x80x94(C1-C6)-alkyl, or xe2x80x94NHxe2x80x94CO-phenyl;
R2 is H, xe2x80x94OH, xe2x80x94CH2OH, or xe2x80x94OMe;
R3 is H, F, methyl, or xe2x80x94OMe;
R4 is xe2x80x94(C1-C16-alkyl), xe2x80x94(C0-C16-alkylene)-R5, xe2x80x94(Cxe2x95x90O)xe2x80x94(C0-C16-alkylene)-R5, xe2x80x94(Cxe2x95x90O)xe2x80x94(C0-C16-alkylene)-NHxe2x80x94R5, xe2x80x94(C1-C8-alkenylene)-R5, xe2x80x94(C1-C8-alkynyl), xe2x80x94(C1-C4-alkylene)-S(O)rxe2x80x94R5, xe2x80x94(C1-C4-alkylene)-Oxe2x80x94R5, or xe2x80x94(C1-C4-alkylene)-NHxe2x80x94R5;
R5 is xe2x80x94COOxe2x80x94R6, xe2x80x94(Cxe2x95x90O)xe2x80x94R6, xe2x80x94(C1-C6-alkylene)-R7, xe2x80x94(C1-C6-alkenylene)-R7, xe2x80x94(C1-C7)-cycloalkyl, phenyl, naphthyl, thienyl, thiophenyl, furanyl, pyridyl, pyrimidyl, dihydropyrimidine-2,4-dion-6-yl, chromanyl, phthalimidoyl, or thiazolyl, wherein the rings are unsubstituted, or substituted up to 3 times by F, Cl, Br, xe2x80x94OH, xe2x80x94CF3, xe2x80x94NO2, xe2x80x94CN, xe2x80x94OCF3, xe2x80x94(C1-C6)-alkyl, xe2x80x94Oxe2x80x94(C1-C6)-alkyl, xe2x80x94Sxe2x80x94(C1-C6)-alkyl, xe2x80x94SOxe2x80x94(C1-C6)-alkyl, xe2x80x94SO2xe2x80x94(C1-C6)-alkyl, xe2x80x94(C1-C6)-alkyl, xe2x80x94(C3-C6)-cycloalkyl, xe2x80x94COOH, xe2x80x94COOxe2x80x94(C1-C6)-alkyl, xe2x80x94COOxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94CONH2, xe2x80x94CONHxe2x80x94(C1-C6)-alkyl, xe2x80x94CON[(C1-C6)-alkyl]2, xe2x80x94CONHxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94NH2, xe2x80x94NHxe2x80x94COxe2x80x94(C1C6)-alkyl, xe2x80x94NHxe2x80x94CO-phenyl, or pyridyl;
R6 is H or xe2x80x94(C1-C6)-alkyl;
R7 is H, xe2x80x94(C1-C7)-cycloalkyl, phenyl, naphthyl, thienyl, thiophenyl, furanyl, pyridyl, pyrimidyl, dihydropyrimidine-2,4-dion-6-yl, chromanyl, phthalimidoyl, or thiazolyl, wherein the rings are unsubstituted, or substituted up to 3 times by F, Cl, Br, xe2x80x94OH, xe2x80x94CF3, xe2x80x94NO2, xe2x80x94CN, xe2x80x94OCF3, xe2x80x94(C1C6)-alkyl, xe2x80x94Oxe2x80x94(C1-C6)-alkyl, xe2x80x94Sxe2x80x94(C1-C6)-alkyl, xe2x80x94SOxe2x80x94(C1-C6)-alkyl, xe2x80x94SO2xe2x80x94(C1-C6)-alkyl, xe2x80x94(C1-C6)-alkyl, xe2x80x94(C3-C6)-cycloalkyl, xe2x80x94COOH, xe2x80x94COOxe2x80x94(C1-C6)-alkyl, xe2x80x94COOxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94CONH2, xe2x80x94CONHxe2x80x94(C1-C6)-alkyl, xe2x80x94CON[(C1-C6)-alkyl]2, xe2x80x94CONHxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94NH2, xe2x80x94NHxe2x80x94COxe2x80x94(C1-C6)-alkyl, or xe2x80x94NHxe2x80x94CO-phenyl;
l, q, m, n, o, p each independently of one another is 0 or 1, where the sum of l+q+m+n+o+p is greater than or equal to 1; and
r is 0, 1, or 2;
with the proviso that in formula (I), when R1 is unsubstituted phenyl, R2 is H, R3 is H, and l, m, n, o, and p are all zero, then R4 is other than xe2x80x94CH3 or xe2x80x94C(CH3)3.
Preferred compounds of formula (I) or salts thereof are those in which one or more radical(s) has or have the following meaning:
Z is
xe2x80x94NHxe2x80x94(C1-C16-alkyl)-(Cxe2x95x90O)xe2x80x94,
xe2x80x94(Cxe2x95x90O)xe2x80x94(C1-C16-alkyl)-(Cxe2x95x90O)xe2x80x94, or
xe2x80x94(Cxe2x95x90O)-phenyl-(Cxe2x95x90O)xe2x80x94;
A1, A2, A3, A4, each independently of one another is an amino acid radical, or an amino acid radical which is mono- or polysubstituted by amino acid-protective groups;
E is xe2x80x94SO2xe2x80x94R4 or xe2x80x94COxe2x80x94R4;
R1 is phenyl, thiazolyl, oxazolyl, thienyl, thiophenyl, furanyl, pyridyl, or pyrimidyl, wherein the rings are unsubstituted or substituted up to 3 times by F, Cl, Br, xe2x80x94OH, xe2x80x94CF3, xe2x80x94NO2, xe2x80x94CN, xe2x80x94OCF3, xe2x80x94(C1-C6)-alkyl, xe2x80x94Oxe2x80x94(C1-C6)-alkyl, xe2x80x94Sxe2x80x94(C1-C6)-alkyl, xe2x80x94SOxe2x80x94(C1-C6)-alkyl, xe2x80x94SO2xe2x80x94(C1-C6)-alkyl, xe2x80x94(C1-C6)-alkyl, xe2x80x94(C3-C6)-cycloalkyl, xe2x80x94COOH, xe2x80x94COOxe2x80x94(C1-C6)-alkyl, xe2x80x94COOxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94CONH2, xe2x80x94CONHxe2x80x94(C1-C6)-alkyl, xe2x80x94CON[(C1-C6)-alkyl]2, xe2x80x94CONHxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94NH2, xe2x80x94NHxe2x80x94COxe2x80x94(C1-C6)-alkyl, or xe2x80x94NHxe2x80x94CO-phenyl;
R2 is H, xe2x80x94OH, xe2x80x94CH2OH, or xe2x80x94OMe;
R3 is H, F, methyl, or xe2x80x94OMe;
R4 is xe2x80x94(C1-C16-alkyl), xe2x80x94(C0-C16-alkylene)-R5, xe2x80x94(Cxe2x95x90O)xe2x80x94(C0-C16-alkylene)-R5, xe2x80x94(Cxe2x95x90O)xe2x80x94(C0-C16alkylene)-NHxe2x80x94R5, xe2x80x94(C1-C8-alkenylene)-R5, xe2x80x94(C1-C8-alkynyl), xe2x80x94(C1-C4-alkylene)-S(O)rR5, xe2x80x94(C1-C4-alkylene)-Oxe2x80x94R5 or xe2x80x94(C1-C4-alkylene)-NHxe2x80x94R5;
R5 is xe2x80x94COOxe2x80x94R6, xe2x80x94(Cxe2x95x90O)xe2x80x94R6, xe2x80x94(C1-C6-alkylene)-R7, xe2x80x94(C1-C6-alkenylene)-R7, xe2x80x94C1-C7)-cycloalkyl, phenyl, naphthyl, thienyl, thiophenyl, furanyl, pyridyl, pyrimidyl, dihydropyrimidine-2,4-dion-6-yl, chromanyl, phthalimidoyl, or thiazolyl, wherein the rings are unsubstituted or substituted up to 3 times by F, Cl, Br, xe2x80x94OH, xe2x80x94CF3, xe2x80x94NO2, xe2x80x94CN, xe2x80x94OCF3, xe2x80x94(C1-C6)-alkyl, Oxe2x80x94(C1-C6)-alkyl, xe2x80x94Sxe2x80x94(C1-C6)-alkyl, xe2x80x94SOxe2x80x94(C1-C6)-alkyl, xe2x80x94SO2xe2x80x94(C1-C6)-alkyl, (C1-C6)-alkyl, xe2x80x94(C3-C6)-cycloalkyl, xe2x80x94COOH, xe2x80x94COOxe2x80x94(C1-C6)-alkyl, xe2x80x94COOxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94CONH2, xe2x80x94CONHxe2x80x94(C1-C6)-alkyl, xe2x80x94CON[(C1-C6)alkyl]2, xe2x80x94CONHxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94NH2, xe2x80x94NHxe2x80x94COxe2x80x94(C1-C6)-alkyl, xe2x80x94NHxe2x80x94CO-phenyl, or pyridyl;
R6 is H or xe2x80x94(C1-C6)-alkyl;
R7 is H, xe2x80x94(C1-C7)-cycloalkyl, phenyl, naphthyl, thienyl, thiophenyl, furanyl, pyridyl, pyrimidyl, dihydropyrimidine-2,4-dion-6-yl, chromanyl, phthalimidoyl, or thiazolyl, wherein the rings are unsubstituted or substituted up to 3 times by F, Cl, Br, xe2x80x94OH, xe2x80x94CF3, xe2x80x94NO2, xe2x80x94CN, xe2x80x94OCF3, xe2x80x94(C1-C6)-alkyl, xe2x80x94Oxe2x80x94(C1-C6)-alkyl, xe2x80x94Sxe2x80x94(C1-C6)-alkyl, xe2x80x94SOxe2x80x94(C1-C6)-alkyl, xe2x80x94SO2xe2x80x94(C1-C6)-alkyl, xe2x80x94(C1-C6)-alkyl, xe2x80x94(C3-C6)-cycloalkyl, xe2x80x94COOH, xe2x80x94COOxe2x80x94(C1-C6)-alkyl, xe2x80x94COOxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94CONH2, xe2x80x94CONHxe2x80x94(C1-C6)-alkyl, xe2x80x94CON[(C1-C6)alkyl]2, xe2x80x94CONHxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94NH2, xe2x80x94NHxe2x80x94COxe2x80x94(C1-C6)-alkyl, or xe2x80x94NHxe2x80x94CO-phenyl;
l is 0 or 1;
m, n are 0;
o is 1;
p is 0 or 1;
q is 0 or 1; and
r is 0, 1, or 2.
Particularly preferred compounds of formula (I) or salts thereof are those in which one or more radical(s) has or have the following meaning:
Z is
xe2x80x94NHxe2x80x94(C1-C12-alkyl)-(Cxe2x95x90O)xe2x80x94,
xe2x80x94(Cxe2x95x90O)xe2x80x94(C1-C12-alkyl)-(Cxe2x95x90O)xe2x80x94, or
xe2x80x94(Cxe2x95x90O)-phenyl-(Cxe2x95x90O)xe2x80x94;
A1, A2, A3, A4 each independently of one another is an amino acid radical, or an amino acid radical which is mono- or polysubstituted by amino acid-protective groups;
E is xe2x80x94SO2xe2x80x94R4 or xe2x80x94COxe2x80x94R4;
R1 is phenyl, thiazolyl, or oxazolyl, wherein the rings are unsubstituted or substituted up to 3 times by xe2x80x94(C1-C6)-alkyl;
R2 is H, xe2x80x94OH, xe2x80x94CH2OH, or xe2x80x94OMe;
R3 is H, F, methyl, or xe2x80x94OMe;
R4 is xe2x80x94(C1-C16-alkyl), xe2x80x94(C0-C16-alkylene)-R5, xe2x80x94(Cxe2x95x90O)xe2x80x94(C0-C16-alkylene)-R5, xe2x80x94(Cxe2x95x90O)xe2x80x94(C0-C16-alkylene)-NHxe2x80x94R5, xe2x80x94(C1-C8-alkenylene)-R5, xe2x80x94(C1-C8-alkynyl), xe2x80x94(C1-C4-alkylene)-S(O)rxe2x80x94R5, xe2x80x94(C1-C4-alkylene)-Oxe2x80x94R5, or xe2x80x94(C1-C4-alkylene)-NHxe2x80x94R5;
R5 is xe2x80x94COOxe2x80x94R6, xe2x80x94(Cxe2x95x90O)xe2x80x94R6, xe2x80x94(C1-C7)-cycloalkyl, phenyl, naphthyl, thienyl, thiophenyl, furanyl, pyridyl, pyrimidyl, dihydropyrimidine-2,4-dion-6-yl, chromanyl, phthalimidoyl, or thiazolyl, wherein the rings are unsubstituted or substituted up to twice by F, Cl, Br, xe2x80x94OH, xe2x80x94CF3, xe2x80x94NO2, xe2x80x94CN, xe2x80x94OCF3, xe2x80x94(C1-C6)-alkyl, xe2x80x94Oxe2x80x94(C1-C6)-alkyl, xe2x80x94COOH, xe2x80x94COOxe2x80x94(C1-C6)-alkyl, xe2x80x94CONH2, xe2x80x94CONHxe2x80x94(C1-C6)-alkyl, xe2x80x94CON[(C1-C6)alkyl]2, xe2x80x94CONHxe2x80x94(C3-C6)-cycloalkyl, xe2x80x94NH2, xe2x80x94NHxe2x80x94COxe2x80x94(C1-C6)-alkyl, xe2x80x94NHxe2x80x94CO-phenyl, or pyridyl;
R6 is H or xe2x80x94(C1-C6)-alkyl;
l, m, n is 0;
o is 1;
p is 0 or 1;
q is 0 or 1; and
r is 0, 1, or 2.
The term alkyl is understood as meaning straight-chain or branched hydrocarbon chains. The phrase xe2x80x9ceach independently of one another isxe2x80x9d means each radical is individually selected without reference to the selection of the other radicals. Therefore, this phrase includes situations where the radicals are all identical to one another, where they are all different from one another, and where some radicals are identical to one another and others are different.
The terms amino acid(s) or amino acid radical(s) mean the stereoisomeric forms, i.e., D- or L-forms, of any of the following compounds:
Abbreviation of the amino acids is in accordance with customary nomenclature (cf. Schrxc3x6der, Lxc3xcbke, The Peptides, Volume I, New York 1965, pages XXII-XXIII; Houben-Weyl, Methoden der Organischen Chemie (Methods of Organic Chemistry), Volume XV/1 and 2, Stuttgart 1974). The amino acid pGlu represents pyroglutamyl, Nal represents 3-(2-naphthyl)alanine, Azagly-NH2 represents a compound of the formula NH2xe2x80x94NH xe2x80x94CONH2 and D-Asp represents the D-form of aspartic acid. Peptides are acid amides in their chemical nature and dissociate into amino acids on hydrolysis.
The present invention furthermore relates to processes for the preparation of compounds of formula (I) which comprise the following reaction equations (Equations 1 to 6).
The compounds of formula (I) and their salts according to the present invention are prepared starting from compounds of formulae VI or VII in stages from the free amino group or by coupling of segments by the general methods of peptide chemistry (Houben-Weyl Methoden der Organischen Chemie, Volume 15/1,2). The peptide couplings can be carried out, for example, with TOTU (for literature examples see: G. Breipohl, W. Kxc3x6nig EP 0460446; W. Kxc3x6nig, G. Breipohl, P. Pokomy, M. Birkner in E. Giralt and D. Andreu (Eds.) Peptides 1990, Escom, Leyden, 1991, 143-145) by the method of mixed anhydrides, via active esters, azides or by the carbodiimide method, in particular with the addition of substances which accelerate the reaction and prevent racemization, such as 1-hydroxybenzotriazole, N-hydroxysuccinimide, 3-hydroxy-4-oxo-3,4-dihydro-1,2,3-benzotriazine, or N-hydroxy-5-norbornene-2,3-dicarboximide, and furthermore using active derivatives of 1-hydroxybenzotriazole or anhydrides of phosphoric, phosphonic and phosphinic acids, at a reaction temperature of between xe2x88x9210xc2x0 C. and the boiling point of the solvent, preferably between xe2x88x925xc2x0 C. and 40xc2x0 C.
Suitable solvents for this are dimethylformamide, dimethylacetamide, N-methylpyrrolidone or dimethyl sulfoxide. If the solubility of the components allows, solvents such as methylene chloride, chloroform or tetrahydrofuran or mixtures of solvents can also be employed. Suitable methods are described in Meinhofer-Gross, xe2x80x9cThe Peptidesxe2x80x9d Academic Press, Volume I, (1979), among others.
If necessary to prevent side reactions, or for the synthesis of specific peptides, the functional groups in the amino acid side chain are additionally protected by suitable protective groups (see, for example, T. W. Greene, xe2x80x9cProtective Groups in Organic Synthesisxe2x80x9d). Primary examples are Arg(BOC)2, Arg(Tos), Arg(Mts), Arg(Mtr), Arg(PMV), Asp(OBzl), Asp(OBut), Cys(4-MeBzl), Cys(Acm), Cys(SBut), Glu(OBzl), Glu(OBut), His(Tos), His(Fmoc), His(Dnp), His(Trt), Lys(Cl-Z), Lys(Boc), Met(O), Ser(Bzl), Ser(But), Thr(Bzl), Thr(But), Trp(Mts), Trp(CHO), Tyr(Br-Z), Tyr(Bzl) or Tyr(But).
The benzyloxycarbonyl (Z) radical, which can be split off by catalytic hydrogenation, the 2-(3,5-dimethyloxyphenyl)propyl(2)oxycarbonyl (Ddz) or trityl (Trt) radical, which can be split off by weak acids, and the 9-fluorenyl-methyloxycarbonyl (Fmoc) radical, which can be split off by secondary amines, are typical examples of useful amino-protective groups. The SH group of cysteine can be blocked by a number of protective groups. The trityl (Trt) radical and the S-tert-butyl (StBu) radical are generally used for this purpose. The trityl radical can be split off by iodine oxidation with formation of the cysteine compounds, or by reducing acid cleavage to give the cysteine compounds (Liebigs Ann. Chem. 1979, 227-247).
On the other hand, the S-tert-butyl radical is best split off reductively with tributylphosphine (Aust. J. Chem. 19 (1966) 2355-2360). OH and COOH functions in the side chains are best protected by the tert-butyl (tBu) radical, which can be split off under acid conditions (see also: Meienhofer-Gross: xe2x80x9cThe Peptidesxe2x80x9d, Volume 3). The compounds of formulae VI and VII are prepared as follows: 
Compounds of type IV are obtained by reacting o-, m- or p-substituted imines of type II with a ketone III. The reaction can be carried out, for example, by mixing the two compounds in bulk, without a solvent, and subsequently heating the mixture, or in a suitable solvent such as ethanol, tetrahydrofuran (THF), toluene, diglyme or tetradecane, at temperatures of from 20xc2x0 C. to 150xc2x0 C.
The keto compounds of type IV are reduced with NaBH4 or other suitable reducing agent in a suitable solvent, such as methanol, THF, or THF/water, at temperatures between xe2x88x9230xc2x0 C. and +40xc2x0 C. to give hydroxy compounds of type V. Two isomer mixtures (racemates) are usually obtained as the main products in the reduction. The different racemates can be separated from one another by fractional crystallization or by silica gel chromatography. The nitro group in compounds of type V can be reduced by known processes, such as, for example, catalytic hydrogenation with Pd or Pd-on-charcoal and H2 in methanol.
The racemic compounds of type VI thus obtained can be separated further into their enantiomers. The racemate splitting of VI into enantiomers of type VII can be carried out by chromatography over chiral column material or by processes which are known from the literature, using optically active auxiliary reagents (cf. J. Org. Chem. 44, 1979, 4891).
In Preparation of compounds of formula (I) according to the present invention starting from compounds of type VI or VII is shown below.
Process A 
Compounds of formula VI or VII are reacted with derivatives of aminoalkanecarboxylic acids. Peptide coupling processes are employed here. The aminoalkanecarboxylic acids, such as xcex2-alanine or xcfx89-aminoundecanoic acid, are protected with Fmoc groups, and corresponding nitro- or azidocarboxylic acids can also be used. After the protective group has been split off in a second step, or correspondingly after reduction of the azido or nitro group, compounds of formula VIII are obtained.
Compounds of formulae VI, VII or VIII can be reacted with amino-protected, for example Fmoc-protected, amino acids by peptide coupling processes, and the side chains can be protected with suitable orthogonal protective groups, or can be unprotected. After the coupling reaction, the protective group of the amino function is split off, in the case of Fmoc, for example, with piperidine in DMF. The compounds of type IX thereby obtained can be reacted in one to three further reaction sequences, i.e., amino acid coupling and splitting off of the amino-protective group, to give compounds of formula X.
The protective groups of the side chains of the amino acids A1 to A4, which number up to four, cain be split off individually after each reaction sequence or together after all the coupling reactions, or all or some of them can also remain on the compounds X according to the present invention.
Process B 
The free amino functions of compounds of formulae VI, VII, VIII, IX or X are reacted with carboxylic acids, also by customary amide formation methods. Functional groups of the starting compounds susceptible to side reactions must be present in protected form, and can be split off after the reaction with the carboxylic acid, if necessary. The compounds according to the present invention of type XI are obtained therefrom.
Process C 
Analogously to process B, the sulfonamide derivatives XII are obtained from the compounds of the formulae VI to IX. Accordingly, the amino functions of the starting compounds can be reacted, for example, with sulfonic acid chlorides in the presence of an auxiliary base in a suitable solvent.
Process D 
Compounds of type XIII can be obtained by reaction of dicarboxylic acid monoalkyl esters with compounds of type VI or VII, X representing an alkyl or a phenyl radical, in accordance with the claims. The reaction is carried out by customary peptide coupling processes. The alkyl ester function is then hydrolyzed to the carboxylic acid in order to obtain compounds of the formula XIV. The compounds XIV can also be obtained directly from the amines of type VI or VII by reaction with dicarboxylic acid anhydrides, for example, succinic anhydride, in the presence of a base. If the carboxylic acid function of the compounds XIV is reacted with amino acid alkyl esters which a protective group may carry in the side chain, compounds of formula XV are obtained. The compounds of formula XVI are in turn prepared therefrom by hydrolysis of the alkyl ester function.
Processes A-D can also be modified such that the compounds according to the reactions may be prepared by reactions on a solid phase. This is shown in process E as a general example.
Process E 
The compound of formula V is coupled to a modified polystyrene resin. For this, the carboxyl group of Carboxy-Tentagel (Rapp, Txc3xcbingen) is reacted with the OH function of the compound VI by esterification methods, for example, DCC or DMAP. The nitro group of compound XVII thus obtained is converted into the amino function by suitable methods, for example, SuCl2 reduction processes. On derivative XVIII, which is bonded to the solid phase, the side chain (E)7xe2x80x94(A4)pxe2x80x94(A3)oxe2x80x94(A2)nxe2x80x94(A1)mxe2x80x94(Z)e is built up to the desired length analogously to the peptide coupling processes already described. In the last step, the compounds of formula (I) according to the present invention are split off from the solid phase by hydrolysis of the ester group under basic conditions.
The radicals described as protective groups of amino acid side chains in the processes described can remain in the compounds according to the present invention or can be split off by known methods (see T. W. Greene, xe2x80x9cProtective Groups in Organic Synthesisxe2x80x9d).
The compounds of formula (I) thus obtained can optionally be converted into their pharmaceutically tolerated salts or physiologically functional derivatives.
Because of their higher solubility in water compared with the starting or base compounds, pharmaceutically tolerated salts are particularly suitable for medical uses. These salts must have a pharmaceutically tolerated anion or cation. Suitable pharmaceutically tolerated acid addition salts of the compounds according to the present invention are salts of inorganic acids, such as hydrochloric, hydrobromic, phosphoric, metaphosphoric, nitric, sulfonic and sulfuric acid, and of organic acids, such as acetic, benzenesulfonic, benzoic, citric, ethanesulfonic, fumaric, gluconic, glycolic, isethionic, lactic, lactobionic, maleic, malic, methanesulfonic, succinic, p-toluenesulfonic, tartaric and trifluoroacetic acid. For medical purposes, the chlorine salt is particularly preferable. Suitable pharmaceutically tolerated basic salts are ammonium salts, alkali metal salts (such as sodium and potassium salts) and alkaline earth metal salts (such as magnesium and calcium salts).
Salts with an anion which is not pharmaceutically tolerated are also included in the scope of the present invention as beneficial intermediate products for the preparation or purification of pharmaceutically tolerated salts and/or for use in non-therapeutic applications, such as in vitro applications.
The term xe2x80x9cphysiologically functional derivativexe2x80x9d used herein designates any physiologically tolerated derivative of a compound according to the present invention, i.e., an ester, which, when administered to a mammal, specifically a human, is capable of forming (either directly or indirectly) such a compound or an active metabolite thereof.
Prodrugs of the compounds according to the present invention are another aspect of the present invention. Such prodrugs can be metabolized in vivo to give a compound according to the invention. These prodrugs of the compounds of formula (I) are, for example esters, amides, aldehydes or alcohols obtainable from carboxy groups, or acyl derivatives like (C1-C6)-alkylcarbonyl, (C1-C6)-alkyloxycarbonyl, or aryl-(C1-C4)-alkyloxycarbonyl derivatives obtainable from acylatable groups including amino groups, imino groups, guanidino groups and amidino groups. These prodrugs can be active themselves or inactive.
The compounds according to the present invention can also exist in various polymorphous forms, for example, as amorphous and crystalline polymorphous forms. All the polymorphous forms of the compounds according to the present invention are included in the scope of the present invention and are a further aspect of the present invention.
All references to xe2x80x9ccompound(s) according to formula (I)xe2x80x9d or xe2x80x9ccompound(s) of formula (I)xe2x80x9d in the prestent invention relate to compound(s) of formula (I) as described above and their salts, solvates and physiologically functional derivatives as described herein.
The amount of a compound according to formula (I) necessary for achieving the desired biological effect depends on a number of factors, for example, the specific compound or salt chosen, the intended use, the mode of administration and the clinical condition of the patient.
In general, the daily dose is in the range from 0.3 mg to 100 mg, typically from 3 mg to 50 mg, per day per kilogram of bodyweight, for example 3-10 mg/kg/day. An intravenous dose can be, for example, in the range from 0.3 mg to 1.0 mg/kg, which can suitably be administered as an infusion of 10 ng to 100 ng per kilogram per minute. Suitable infusion solutions for this purpose can comprise, for example, from 0.1 ng to 10 mg, typically from 1 ng to 10 mg per milliliter. Individual doses can comprise, for example, from 1 mg to 10 g of the active compound. Thus, ampoules for injections can contain, for example, from 1 mg to 100 mg, and individual dose formulations for oral administration, such as, for example, tablets or capsules, can contain, for example, from 1.0 to 1000 mg, typically from 10 to 600 mg. In the case of pharmaceutically tolerated salts, the abovementioned weight data relate to the weight of the benzothiazepine ion derived from the salt. For prophylaxis or treatment of the abovementioned conditions, the compounds according to formula (I) can be used directly, but they are preferably present together with a tolerated excipient in the form of a pharmaceutical composition. The excipient must of course be tolerated in the sense that it is compatible with the other constituents of the composition and does not harm the health of the patient. The excipient can be a solid or a liquid or both and is preferably formulated with the compound as an individual dose, for example as a tablet, which can comprise from 0.05 to 95% by weight of the active compound. Further pharmaceutically active substances can also be present, including further compounds according to formula (I). The pharmaceutical compositions according to the present invention can be prepared by one of the known pharmaceutical methods, which substantially comprise mixing the constituents with pharmacologically tolerated excipients and/or auxiliaries.
Pharmaceutical compositions according to the present invention are those which are suitable for oral, rectal, topical, peroral (for example sublingual) and parenteral (for example subcutaneous, intramuscular, intradermal or intravenous) administration, although the most suitable mode of administration in each individual case depends on the nature and severity of the condition to be treated, and on the nature of the particular compound according to formula (I) used. Coated formulations and coated sustained-release formulations are also included in the scope of the present invention. Formulations which are resistant to acid and to gastric juice are preferred. Suitable coatings which are resistant to gastric juice include cellulose acetate phthalate, polyvinyl acetate phthalate, hydroxypropylmethyl-cellulose phthalate, and anionic polymers of methacrylic acid and methyl methacrylate.
Suitable pharmaceutical compounds for oral administration can be present in separate units, such as, for example, capsules, cachets, sucking tablets or tablets, each of which comprises a certain amount of the compound according to formula (I); as powders or granules; as a solution or suspension in an aqueous or non-aqueous liquid; or as an oil-in-water or water-in-oil emulsion. As already mentioned, these compositions can be prepared by any suitable pharmaceutical method which comprises a step in which the active compound and the excipient (which can consist of one or more additional constituents) are brought into contact. The compositions are in general prepared by uniform and homogeneous mixing of the active compound with a liquid and/or finely divided solid excipient, after which the product is shaped, if necessary. Thus, for example, a tablet can be prepared by pressing or shaping a powder or granules of the compound, optionally with one or more additional constituents. Pressed tablets can be prepared by tableting the compound in a free-flowing form, such as, for example, a powder or granules, optionally mixed with a binder, lubricant, inert diluent and/or one (or more) surface-active/dispersing agents, in a suitable machine. Shaped tablets can be prepared by shaping the pulverulent compound, which has been moistened with an inert liquid diluent, in a suitable machine.
Pharmaceutical compositions which are suitable for peroral (sublingual) administration include: sucking tablets, which comprise a compound according to formula (I) with a flavoring substance, usually sucrose, and gum arabic or tragacanth; and pastilles, which comprise the compound in an inert base, such as gelatin and glycerol, or sucrose and gum arabic.
Suitable pharmaceutical compositions for parenteral administration include sterile aqueous formulations of a compound according to formula (I), which are normally isotonic with the blood of the intended recipient. These formulations are generally administered intravenously, although the administration can also take place subcutaneously, intramuscularly or intradermally as an injection. These formulations are generally prepared by mixing the compound with water and rendering the resulting solution sterile and isotonic with blood. Injectable compositions according to the present invention in general comprise 0.1 to 5% by weight of the active compound.
Suitable pharmaceutical compositions for rectal administration are preferably in the form of individual-dose suppositories. These can be prepared by mixing a compound according to formula (I) with one or more conventional solid excipients, for example, cacao butter, and introducing the mixture formed into a mold.
Suitable pharmaceutical compositions for topical use on the skin are preferably in the form of an ointment, cream, lotion, paste, spray, aerosol or oil. Vaseline, lanolin, polyethylene glycols, alcohols and combinations of two or more of these substances can be used as excipients. The active compound is in general present in a concentration of 0.1 to 15% by weight of the composition, for example, 0.5 to 2%.
Transdermal administration is also possible. Suitable pharmaceutical compositions for transdermal applications can be in the form of individual patches which are suitable for long-term close contact with the epidermis of the patient. Such patches suitably comprise the active compound in an optionally buffered aqueous solution, dissolved and/or dispersed in an adhesion promoter or dispersed in a polymer. A suitable active compound concentration is about 1% to 35%, preferably about 3% to 15%. As a particular possibility, the active compound can be released by electroporation or iontophoresis, as described, for example, in Pharmaceutical Research, 2(6): 318 (1986).
The present invention furthermore relates both to isomer mixtures of formula (I) and to the pure enantiomers of formula (I).
The compounds of formula (I) and their pharmaceutically tolerated salts and physiologically functional derivatives thereof are ideal pharmaceuticals for treatment of disturbances in lipid metabolism, in particular, hyperlipidemia. The compounds of formula (I) are also suitable for influencing the serum cholesterol level and for prevention and treatment of arteriosclerotic symptoms. The following findings demonstrate the pharmacological activity of the compounds according to the present invention.
Biological testing of the compounds according to the present invention was carried out by determining the inhibition of [3H]-taurocholate uptake in brush border membrane vesicles of the ileum of rabbits. The inhibition test was carried out as follows:
1. Preparation of Brush Border Membrane Vesicles from the Ileum of Rabbits
Brush border membrane vesicles from the intestinal cells of the small intestine were prepared by the so-called Mg2+ precipitation method. Male New Zealand rabbits (2 to 2.5 kg body weight) were sacrificed by intravenous injection of 0.5 ml T61(copyright), an aqueous solution of 2.5 mg tetracaine HCl, 100 m embutramide and 25 mg mebezonium iodide. The small intestine was removed and rinsed with ice-cold physiological saline solution. The terminal 7/10 of the small intestine (measured in the oral-rectal direction, i.e., the terminal ileum, which contains the active Na+-dependent bile acid transportation system) was used for preparation of the brush border membrane vesicles. The intestines were frozen in plastic bags under nitrogen at xe2x88x9280xc2x0 C. For preparation of the membrane vesicles, the frozen intestines were thawed at 30xc2x0 C. in a water bath. The mucosa was scraped off and suspended in 60 ml of ice-cold 12 mM TRIS/HCl buffer (pH 7.1)/300 mM mannitol, 5 mM EGTA/10 mg/l of phenylmethylsulfonyl fluoride/1 mg/l of trypsin inhibitor from soybeans (32 U/mg)/0.5 mg/l of trypsin inhibitor from bovine lung (193 U/mg)/5 mg/l of bacitracin. After dilution to 300 ml with ice-cold distilled water, the mixture was homogenized with an Ultraturrax (18-rod, IKA Werk Staufen, Germany) for 3 minutes at 75% of the maximum output by cooling with ice. After addition of 3 ml of 1 M MgCl2 solution (final concentration 10 mM), the mixture was allowed to stand for exactly 1 minute at 0xc2x0 C. The cell membranes aggregate by addition of Mg2+ and precipitate, with the exception of the brush border membranes. After centrifugation at 3000xc3x97g (5000 rpm, SS-34 rotor) for 15 minutes, the precipitate was discarded land the supernatant, which contains the brush border membranes, was centrifuged at 48000xc3x97g (20000 rpm, SS-34 rotor) for 30 minutes. The supernatant was discarded, and the precipitate was rehomogenized in 60 ml of 12 mM TRIS/HCl buffer (pH 7.1)/60 mM mannitol, 5 mM EGTA with a Potter Elvejhem homogenizer (Braun, Melsungen, 900 rpm, 10 strokes). After addition of 0.1 ml of 1 M MgCl2 solution and incubation for 15 minutes at 0xc2x0 C., centrifugation was again carried out at 3000xc3x97g for 15 minutes. The supernatant was then centrifuged again at 48000xc3x97x g (20000 rpm, SS-34 rotor) for 30 minutes. The precipitate was taken up in 30 ml of 10 mM TRIS/HEPES buffer (pH 7.4)/300 mM mannitol and resuspended homogeneously by 20 strokes in a Potter Elvejhem homogenizer at 1000 rpm. After centrifugation at 48000xc3x97g (20000 rpm, SS-34 rotor) for 30 minutes, the precipitate was taken up in 0.5 to 2 ml of TRIS/HEPES buffer (pH 7.4)/280 mM mannitol (final concentration 20 mg/ml) and resuspended with the aid of a Tuberculin syringe with a 27-gauge needle. The vesicles were either used for transportation investigations directly after preparation or stored at xe2x88x92196xc2x0 C. in 4 mg portions in liquid nitrogen.
2. Inhibition of the Na+-dependent [3H]taurocholate Uptake in Brush Border Membrane Vesicles of the Ileum
The uptake of substrates in the brush border membrane vesicles described above was determined by means of the so-called membrane filtration technique. 10 xcexcl of the vesicle suspension (100 xcexcg of protein) were pipetted as drops onto the wall of a polystyrene incubation tube (11xc3x9770 mm) which contained the incubation medium with the corresponding ligands (90 xcexcl). The incubation medium comprised 0.75 xcexcl=0.75 xcexcCi [3H(G)]-taurocholate (specific activity: 2.1 Ci/mmol)/0.5 xcexcl of 10 mM taurocholate/8.75 xcexcl of sodium transportation buffer (10 mM TRIS/HEPES (pH 7.4)/100 mM mannitol/100 mM NaCl) (Na-T-P) or 8.75 xcexcl of potassium transportation buffer (10 mM TRIS/HEPES (pH 7.4)/100 mM mannitol/100 mM KCl) (K-T-P) and 80 xcexcl of the inhibitor solution in question, dissolved in Na-T buffer or K-T-buffer, depending on the experiment. The incubation medium was filtered through a polyvinylidenefluoride membrane filter (SYHV LO 4NS, 0.45 xcexcm, 4 mm Ø, Millipore, Eschborn, Germany). Mixing the vesicles with the incubation medium started the transportation measurement. The concentration of taurocholate in the incubation batch was 50 xcexcM. After the desired incubation time (usually 1 minute), the transportation was stopped by addition of 1 ml of ice-cold stopping solution (10 mM TRIS/HEPES (pH 7.4)/150 mM KCl). The mixture formed was immediately filtered with suction under a vacuum of between 25 and 35 mbar over a membrane filter of cellulose nitrate (ME 25, 0.45 xcexcm, 25 mm diameter, Schleicher and Schuell, Dassell, Germany). The filter was rinsed with 5 ml of ice-cold stopping solution.
To measure the uptake of the radioactively labeled taurocholate, the membrane filter was dissolved with 4 ml of the scintillator Quickszint 361 (Zinsser Analytik GmbH, Frankfurt, Germany) and the radioactivity was measured by liquid scintillation measurement in a TriCarb 2500 measuring apparatus (Canberra Packard GmbH, Frankfurt, Germany). The values measured were obtained as dpm (decompositions per minute) after calibration of the apparatus with the aid of standard samples and after correction for any chemiluminescence present.
The control values were each determined in Na-T-P and K-T-P. The difference between the uptake in Na-T-P and K-T-P gave the Na+-dependent transportation content. The concentration of inhibitor at which the Na+-dependent transporation content was inhibited by 50% as compared to the control is designated the IC50 Na+.
The pharmacological data comprise a test series in which the interaction of the compounds according to the present invention with the intestinal bile acid transportation system in the terminal small intestine was investigated. The results are summarized in Table 1.
Table 1 shows measurement values of the inhibition of the [3H]-taurocholate uptake in brush border membrane vesicles of the ileum of rabbits. The quotients of the IC50Na values of the reference substance as taurochenodeoxycholate (TCDC) and of the particular test substance are stated.
The following examples serve to illustrate the present invention in more detail, without limitation to the products and embodiments described in the examples.